Big change in quickfix tests: no stupid test data format with "before" and "after" file prefixes

idea/testData/quickfix/createFromUsage/createVariable/property/refInStringTemplateRuntime.kt

@@ -0,0 +1,6 @@
+// "Create property 'foo'" "true"
+// ERROR: Property must be initialized
+
+fun test() {
+    println("a = $<caret>foo")
+}